Fire protection for buildings

ABSTRACT

A heat and fire protection system and methods of protecting structural elements and assemblies from heat and fire. When a steel structure is erected vertical columns of the structure typically comprise I-sections. In order to provide fire protection for the I-sections and so improve the resistance to fire of the steel structure a column protection system has been developed. The column protection system includes column protection elements which are placed around an I-section. The column protection elements are secured to the I-section. Horizontal beams can also be protected by the column protection system.

PRIORITY CLAIM

The present application is a National Phase entry of PCT Application No.PCT/GB2011/050626, filed Mar. 28, 2011, which claims priority from GreatBritain Application No. 1007259.3, filed ______, the disclosures ofwhich are hereby incorporated by reference herein in their entirety.

FIELD OF THE INVENTION

This invention relates to a fire protection system for a buildingstructure, in particular, but not limited to, a fire protection systemfor a steel frame structure.

BACKGROUND OF THE INVENTION

Steel structures typically form the main strength and support in modernbuildings. Consequently, it is very important to protect such a steelstructure in the event of a fire. If the steel structure is subject toexcessive heat then the structure can fail causing the collapse of thebuilding.

A previous attempt at protecting a steel structure consisting of aplurality of circular hollow section columns has been made by applyingan intumescent material coated onto the external surfaces of thecolumns. In the event of a fire the intumescent material expands andprovides some heat resistance to fire.

A disadvantage of such a system is that a space of at least 50 mm mustbe left between the metal casing and any objects placed close to it toensure that the intumescent material can expand and function properly.

SUMMARY OF THE INVENTION

It is a feature and advantage of the present invention to address theabove mentioned disadvantage.

According to an aspect of the present invention there is provided aheat/fire protection system for a structural assembly comprising aplurality of cover elements, each of the cover elements comprising anattachment portion and a body portion, wherein the body portion providesboth structural rigidity and heat/fire protection.

The heat/fire protection system is preferably a heat/fire protectionsystem for a structural assembly, preferably an assembly of steelcolumns and beams. The heat/fire protection system may be a heat/fireprotection system for columns.

The body portion can be adapted to provide heat/fire protection to asteel column or beam, such as, for example, an I-section or I-beam.

The body portion can be adapted to withstand temperatures in excess ofthose that can be withstood by steel before failure. In one particularembodiment, the body portion is adapted to withstand temperatures inexcess of 550° C. before failure.

The body portion can be made of a polymeric material, which may beglass-reinforced.

Alternatively, the body portion can be made of a ceramic material.

In one particular embodiment, the body portion is self-supporting.

The cover elements are adapted to surround elements of the structuralassembly. More particularly, two cover elements are adapted to cover acircumference of one of the elements of the structural assembly.

The cover elements can be adapted to fit end to end, to thereby coverthe length of an element of the structural assembly using a plurality ofcover elements.

The cover elements can include interengaging projections and recesses orcut-outs to allow two cover elements to surround an element of thestructural assembly and engage with one another. The projections andrecesses/cut-outs can be on peripheral edges, and more particularlylongitudinal peripheral edges, of the cover elements.

The cover elements can be provided in lengths of approximately 1 m to 2m, for example.

The attachment portion can comprise a plurality of attachment elements.

The attachment portion can comprise resilient hook portions, which canbe attachment elements adapted to engage an element of the structuralassembly or another cover element.

In a particular embodiment, the cover elements are adapted to snap fitonto the element of the structural assembly or the other cover element.

The resilient hooks can be curved with a tip pointing towards the bodyportion.

The resilient hooks can be located on edges, and more particularlylongitudinal edges, of the body portion.

The attachment portion can be a collar, and more particularly beingadapted to be secured to a structural member, such as an I-section orI-beam.

Each cover element can include at least two collars, and moreparticularly adapted to be located at or close to opposite ends of anelement of the structure to be protected.

In a particular embodiment, the attachment portion is adapted to receivethe body portion on an exterior face thereof.

In a particular embodiment, the body portion is a sleeve, which can beadapted to engage the attachment portion. Particularly, the body portionis secured to the attachment portion.

The body portion can include at least one end portion adapted to belocated at an end of the sleeve. The at least one end portion can bemade of a molded material, which can be the same material as the bodyportion. The at least one end portion advantageously provides a firestop, to prevent a fire spreading into the interior of the body portion.

The cover element can be adapted to leave ends of a structural elementuncovered, which ends can have an intumescent material applied thereto.

The inner section can be a thermal insulation material, such as rockwool or mineral wool or other insulating material. The inner section canbe in a preformed shape, adapted to fit between a structural member andthe outer section.

The outer section can be made of a material that holds its shape. In aparticular embodiment, the outer section is adapted to protect the innersection from a blast in a fire or other emergency situation.

Alternatively, the inner section can be chosen for its rigidity, i.e. tohold its shape, with the outer section being an intumescent material.The inner section can comprise a self-supporting material.

Embodiments of the invention extend to a structural member, which can bea beam or column, and more particularly an I-section or I-beam, having acover element as described above located thereon.

Embodiments of the invention extend to a cover element as described inthe above aspect.

Embodiments of the invention extend to a structure comprising a fireprotection system and a structural assembly as described above.

According to another aspect of the present invention there is provided amethod of protecting a structural assembly from heat/fire, the methodcomprising fitting a plurality of cover elements to the structuralelements assembly, wherein body portions of the cover elements provideboth structural rigidity to the cover elements and heat/fire protectionto the structural assembly.

The reference to heat/fire should be taken to extend to protection fromfire and/or heat.

According to another aspect of the present invention there is provided amethod manufacturing a protected structural member comprising securingat least one attachment portion to a structural element, and securing abody section over the at least one attachment portion, wherein the bodyportion provides both structural rigidity and heat/fire protection.

All of the features disclosed herein can be combined with any of theabove aspects, in any combination.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention, and to show how embodimentsof the same may be carried into effect, reference will now be made, byway of example, to the accompanying diagrammatic drawings in which:

FIG. 1 is a schematic cross-sectional view from above of a structuralI-section having two column protection elements secured theretoaccording to an embodiment of the invention;

FIG. 2 is a schematic perspective side view of one of the columnprotection elements of FIG. 1 showing attachment clips thereof;

FIG. 3 is a schematic cross-sectional view from above, according toanother embodiment of a column protection system;

FIG. 4 is a schematic view of a structural assembly having a columnprotection system in position according to an embodiment of theinvention;

FIG. 5 is schematic perspective view of a bracket, according to analternative embodiment of column protection;

FIG. 6 is a schematic cross-sectional view of FIG. 5;

FIG. 7 is a schematic perspective view of a completed form of thealternative embodiment of column protection; and

FIG. 8 is a schematic cross-sectional view of FIG. 7.

DETAILED DESCRIPTION OF THE DRAWINGS

When a steel structure is erected, vertical columns of the structuretypically comprise I-sections. In order to provide fire protection forthe I-sections and to improve the resistance to fire of the steelstructure a column protection system has been developed.

Referring to FIGS. 1 and 2, the column protection system 8 comprisescolumn protection elements 10 a and 10 b which are placed around anI-section 12 the column protection elements 10 a and 10 b secure to theI-section 12 by means of clips 14 a (see FIG. 2). Horizontal beams canalso be protected by the column protection system.

The column protection elements 10 a and 10 b are made of a polymericmolding material, which can be glass reinforced. An alternative materialwould be to use a ceramic material. The benefits of the material usedare that it is stable under heat and doesn't intumesce.

The benefits of such materials are also that they can be drilled, sawnand glued, as appropriate. The material is also impact resistant.

The column protection elements are typically provided in lengths ofapproximately 1 m to 1.5 m. This would allow the usual height betweenfloors of an I-section column of 3 m to be protected with a number oflengths of the column protection elements secured along the column.

In more detail, the column protection elements 10 a/b have a curvedbody, an outer wall of which may be semi-circular or form a semi-oval incross-section. Of course other shapes can be used also.

Interengaging fingers 16 a and 16 b are provided on each of the columnprotection elements 10 a and 10 b, which fingers 16 a, 16 b allow thecolumn protection elements 10 a, 10 b to mate and form a close fit withone another when placed in the positions, shown in FIG. 1, for example.

The clips 14 a can be provided on wedge supports 18. The wedge supportsprovide a location for the clips 14 a to be secured to the main body ofthe column protection elements 10 a,b. The wedges 18 also allow thespacing between the clips to be set so that adjacent clips on oppositesides of a column protection element 10 a/b can receive a flange of theI-section 12 between them.

As can be seen in FIG. 1, the clips 14 a are curved and point towards amain body of the column protection element. This has been done so thatwhen a concave side of a column protection element is pushed towards aflange of an I-section the column protection element can be pushed ontothe I-section causing the clips 14 a to be pushed to the side to allowthe column protection element to engage the flange of the I-section.Once passed the flange, the clips 14 can spring back into their originalposition. As can be seen from FIG. 1 in the secured position, the clipsretain the column protection element in position relative to theI-section 12. Another column protection element is secured to theopposite flange of the I-section in the same way.

As can be seen from FIG. 1, the fingers 16 a and 16 b interdigitate tocause the two column protection elements 10 a and 10 b to engage withone another and form a continuous external surface around the I-section12. The continuous external surface provides excellent fire protection.

With the column protection system described above, an externaltemperature outside the column protection elements can be 1000° C.,whilst still retaining a temperature of below 550° C. at the I-section.Consequently, excellent fire protection is provided by the systemdescribed. Protection for at least two hours in a fire situation isprovided.

An alternative embodiment for securing the column protection elements 10a and 10 b to the I-section is shown in FIG. 3. Like numerals have beenused where like parts are used.

In this embodiment instead of the clips 14 a being used to secure thecolumn protection elements 10 a and 10 b to the I-section the clips areused to secure the two column protection elements 10 a and 10 b to eachother. Similar clips are provided to those described in relation toFIGS. 1 and 2, but the location of those clips is changed to peripheraledges of the column protection elements 10 a and 10 b. The two clips 14a engage with one another to secure the two column protection elements10 a and 10 b together around the I-section 12. A clip on one side mayalternatively engage with a flange on the other side.

In other respects the embodiment shown in FIG. 3 functions and is usedin the same way as the embodiment shown in FIGS. 1 and 2.

FIGS. 5 to 8 show a third embodiment of column protection system. Inthis embodiment, collars 30 are secured to the I-section 12, forexample, with brackets 32 secured to flanges of the I-section 12.

The collars 30 are in the form of a ring, which can be circular, or canbe oval. The collars receive a sleeve 34, which is secured to thecollars 30, for example, with adhesive or with fixing means. The sleeve34 is made of the same material as the column protection elements 10 aand 10 b mentioned in relation to the first embodiment.

End pieces 36 a-d are inserted into both open ends of the sleeve 34, toclose the gap between the sleeve 34 and the I-section 12. The end pieces36 a-d can be made of the same material as the sleeve 34, which meansthat they are advantageously moldable. The end pieces 36 a-d provide afire-stop to prevent the passage of fire between the I-section and thesleeve 34. Alternative fire-stopping material can also be used, as arewell known in the art.

The exposed ends of the I-section 12 are then coated with an intumescentmaterial.

The columns can be prepared off-site, which reduces labor costs comparedto fitting a column protection system on site.

A variant on this system is to fill the sleeve 34 with insulatingmaterial such as rock wool or mineral wool, which could be provided inpre-formed shapes to slide inside the sleeve 34.

The thickness of the sleeve 34 is chosen to suit a particular purpose.For example a thicker sleeve 34 can be 70 mm thick, where it is to beused in a car park to have some impact protection, or another locationwhere impacts are likely.

The sleeve can be 10-25 mm thick where there is less chance of animpact, but insulation is less likely to be needed or used.

For a thin version the sleeve can be 5 to 10 mm thick to provide someblast protection with heat protection being given by insulation.

A further alternative is to have a sleeve of substantially rigid, orself-supporting, material that will hold its shape. An intumescentmaterial is applied to the sleeve to provide protection from fire. Inthis alternative embodiment, space must be left around the protectedcolumn to allow for expansion of the intumescent material in a firesituation.

Embodiments of the invention can also be used for elements other thancolumns, such as horizontal or diagonal beams. Also, the beams need notbe I-sections. In particular, the second or third embodiments could beused around any shape of beam.

Attention is directed to all papers and documents which are filedconcurrently with or previous to this specification in connection withthis application and which are open to public inspection with thisspecification, and the contents of all such papers and documents areincorporated herein by reference.

All of the features disclosed in this specification (including anyaccompanying claims, abstract and drawings), and/or all of the steps ofany method or process so disclosed, can be combined in any combination,except combinations where at least some of such features and/or stepsare mutually exclusive.

Each feature disclosed in this specification (including any accompanyingclaims, abstract and drawings) can be replaced by alternative featuresserving the same, equivalent or similar purpose, unless expressly statedotherwise. Thus, unless expressly stated otherwise, each featuredisclosed is one example only of a generic series of equivalent orsimilar features.

The invention is not restricted to the details of the foregoingembodiment(s). The invention extends to any novel one, or any novelcombination, of the features disclosed in this specification (includingany accompanying claims, abstract and drawings), or to any novel one, orany novel combination, of the steps of any method or process sodisclosed.

1. A heat/fire protection system for a structural assembly, theheat/fire protection system comprising: a plurality of cover elements,each of the cover elements including an attachment portion and a bodyportion, wherein the body portion provides both structural rigidity andheat/fire protection.
 2. The heat/fire protection system of claim 1,which is a heat/fire protection system for a structural assembly ofcolumns and beams.
 3. The heat/fire protection system of claim 1,wherein the body portion is adapted to provide heat/fire protection to asteel column or beam.
 4. The heat/fire protection system of claim 1,wherein the body portion is adapted to withstand temperatures in excessof those that can be withstood by steel before failure.
 5. The heat/fireprotection system of claim 1, wherein the body portion isself-supporting.
 6. The heat/fire protection system of claim 1, whereinthe cover elements are adapted to surround elements of the structuralassembly.
 7. The heat/fire protection system of claim 1, wherein thecover elements include interengaging projections and recesses orcut-outs to allow two cover elements to surround an element of thestructural assembly and engage with one another.
 8. The heat/fireprotection system of claim 1, wherein the attachment portion is a collaradapted to be secured to a structural member.
 9. The heat/fireprotection system of claim 1, wherein the cover element comprise innerand outer sections.
 10. The heat/fire protection system of claim 9,wherein the inner section is a thermal insulation material.
 11. Theheat/fire protection system of claim 10, wherein the inner section is ina preformed shape, adapted to fit between a structural member and theouter section.
 12. A structural member, optionally a beam or column,incorporating a cover element as claimed in claim
 1. 13. A cover elementas claimed in claim
 1. 14. A structure comprising a fire protectionsystem and a structural assembly as claimed in claim
 1. 15. A method ofprotecting a structural assembly comprising a plurality of structuralelements from heat/fire, the method comprising: fitting a plurality ofcover elements to the structural elements of the structural assembly,wherein body portions of the cover elements provide both structuralrigidity to the cover elements and heat/fire protection to thestructural assembly.
 16. A method of manufacturing a protectedstructural member comprising: securing at least one attachment portionto a structural element; and securing a body section over the at leastone attachment portion, wherein the body portion provides bothstructural rigidity and heat/fire protection.
 17. The heat/fireprotection system of claim 8, wherein the structural member comprises anI-section.
 18. The heat/fire protection system of claim 10, wherein thethermal insulation material comprises rock wool or mineral wool.